System for positioning cladding panels, reinforced soil structure comprising said system and associated positioning method

ABSTRACT

The invention relates to a system for positioning cladding panels, a reinforced soil structure comprising said device and an associated positioning method. The system comprises at least first and second cladding panels and at least one separator interposed between said cladding panels. The separator has elastic properties configured to maintain a relative reference position (Pr) between the first and second cladding panels. The separator is capable of being deformed under the effect of a stress applied to the separator by the first and second cladding panels, causing the second and first cladding panels to move closer together when the stress is greater than a predefined threshold.

TECHNICAL FIELD

The invention relates to the field of positioning of cladding panels for the purpose of optimizing their settling, in particular in the context of cladding panels which are arranged in structures of the reinforced ground structure type.

TECHNOLOGICAL BACKGROUND

Reinforced ground structures traditionally comprise cladding panels, a backfill which fills a rear side of the cladding panels, reinforcement elements distributed in the backfill in order to stabilize it mechanically, and a system for connection between the reinforcement elements and the cladding panels.

The cladding panels can for example be produced from prefabricated concrete elements in the form of slabs or blocks, said prefabricated elements being juxtaposed in order to cover the frontal face of the works. Works thus produced are known in particular under the commercial reference TerraClass® by the company TERRE ARMEE INTERNATIONALE.

Other structures are based on the use of cladding panels produced from a grid or lattice, in particular constituted by metal rods which are welded to one another or woven. A structure incorporating lattices of this type in the form of cladding panels can also comprise a geotextile, and can be vegetated. Works thus produced are known in particular under the commercial name TerraTrel® by TERRE ARMEE INTERNATIONALE.

During the construction of a reinforced ground structure, the cladding panels are subjected to settling under the effect of the pressure exerted by the backfill, as the structure gains height. In order to anticipate this settling, it is common to install the cladding panels progressively row by row, with each row defining a level of height equal to that of a cladding panel. A space of around 10 cm, typically approximately 4 cm, is provided between two cladding panels belonging to adjacent rows, in order to permit progressive settling of the cladding panels when the backfill is added to the rear side of the cladding panels.

However, this space can close rapidly when the backfill is added to the structure. In order to avoid premature settling of the cladding panels, it is common to use a wooden wedge installed in the space between two rows of cladding panels. A wooden wedge of this type slows down the settling of the cladding panels for height of backfill corresponding typically to 2 or 3 levels above the space between two rows.

However, the use of these wooden wedges has many disadvantages.

Firstly, the wooden wedge must be removed manually before the backfill reaches a critical height, above which the stresses exerted by the result in settling which deforms the wedge irreversibly. The wedge is then trapped between two cladding panels. When a wooden wedge remains trapped between two cladding panels, it can no longer be removed, and disfigures the external appearance of the front side of the cladding panels.

In addition, the presence of wooden wedges trapped between two cladding panels can create a hard point in the reinforced ground structure. A hard point of this type blocks the settling of the cladding panels, and can lead to flexure deformation of the cladding panels. This deformation damages the reinforced ground structure.

In order to avoid these disadvantages, the wooden wedges need to be removed at the appropriate time during the construction of the reinforced ground structure. This additional step constitutes an extra labor cost, and can be dangerous for the workers who are forced to operate on the front side of the cladding panels in order to remove the wedges. The removal of the wooden wedges can require interventions at heights of over 30 m on certain sites.

A device for positioning of cladding panels is consequently required which makes it possible to control the settling of the cladding panels, whilst avoiding the occurrence of hard points which can deform the cladding panels.

SUMMARY OF THE INVENTION

In order to solve the above-described problems, the present invention proposes a device for positioning cladding panels, comprising:

-   -   at least a first cladding panel and a second cladding panel;     -   at least one separator interposed between the first cladding         panel and the second cladding panel;         wherein the separator has resilient properties which are         configured to maintain a relative reference position between the         first and second cladding panels, the separator being able to         undergo progressive resilient deformation under the effect of a         stress exerted on the separator by the first and second cladding         panels, thus giving rise to moving closer together of the first         cladding panel and the second cladding panel when the stress is         greater than a predefined threshold.

The expression “positioning device” can be replaced in an equivalent manner by the expression “positioning system”, with these two expressions designating the assembly formed by the first and second cladding panels and the separator.

A separator with resilient properties configured to allow two cladding panels to be moved closer together for stresses greater than a predefined threshold prevents the formation of hard points. In addition, unlike the wooden wedges of the prior art, a separator with resilient properties as defined above no longer needs to be removed after settling of the cladding panels. The predefined threshold above which the first and second cladding panels start to move closer together can typically be equal to, or more than, the weight of a cladding panel.

According to one embodiment, the first cladding panel and the second cladding panel are lattices.

According to one embodiment, the device can also comprise:

-   -   at least one connection element connecting the first cladding         panel to the second cladding panel, the connection element being         configured to exert a pre-stressing force compressing the         separator and maintaining the relative reference position         between the first and second cladding panels, for as long as the         stress is lower than the predefined threshold.

The pre-stressing force which the connection element exerts on the first and second cladding panels corresponds to a reaction force which compensates for the compression forces initially exerted on the cladding panels. These forces correspond to a stress comprising a reaction force which is substantially equal to the weight of the second cladding panel, and a compression force exerted by the backfill situated above the separator. The predefined threshold can be such that the relative reference position is maintained for a height of backfill above the separator of less than 2 rows of cladding panels. As a result of the pre-stressing force, no settling of the first and second cladding panels then takes place for a stress lower than the predefined threshold.

According to one embodiment, the connection element can be selected from amongst: a metal wire, a looped hooked connector, a connector in the form of a “U”.

According to one embodiment, the separator can be in the form of a spring.

In particular, the spring can be able to be compressed until it reaches a thickness equal to the thickness of a turn of the spring.

In particular, the spring can be selected from amongst: a conical spring and a bi-conical spring.

Springs of this type permit maximum moving closer together of the first and second cladding panels, providing the best compressibility under the effect of the action of the backfill. A bi-conical spring can also more easily be connected to the first and second cladding panels because of its ends with dimensions which are substantially equal and reduced.

According to one embodiment, the spring can be in the form of a strip, a first end of which is connected to the first cladding panel, and a second end of which is connected to the second cladding panel, the strip having a curvature which is a variable under the effect of the stress.

A strip of this type can easily be installed on latticed panels, and ensures stability of the cladding panels before the backfill is added.

According to one embodiment, the second cladding panel has a bar forming a recess in the form of an “L”, the variable curvature of the strip forming a spring which is supported on said bar.

By allowing the strip to be supported on a recess in the form of an “L”, an even more stable connection is ensured between the cladding panels before the backfill is added.

According to one embodiment, the separator has a first end connected to a higher reference bar of the first cladding panel, and a second end connected to a lower reference bar of the second cladding panel.

According to one embodiment, the predefined threshold is reached for a stress corresponding to the weight of a mass of 10 to 20 kg.

The invention also relates to a reinforced ground structure comprising a device as previously described, the structure additionally comprising a plurality of cladding panels arranged above one another, each panel of the plurality comprising a front face and a rear face, the structure additionally comprising:

-   -   backfill disposed on the side of the rear face of the panels of         the plurality of cladding panels,         the stress being proportional to a height of backfill in the         reinforced ground structure, the predefined threshold being         reached when the backfill covers a height above the first         cladding panel corresponding to two cladding panels.

The invention also relates to a method for positioning cladding panels, comprising:

-   -   installing at least a first cladding panel and a second cladding         panel separated from the first cladding panel by a separator         with resilient properties configured to maintain a relative         reference position between the first cladding panel and the         second cladding panel;     -   exerting a stress on the separator by means of the first         cladding panel and the second cladding panel, such that the         separator is deformed, giving rise to moving closer together of         the first cladding panel and the second cladding panel when the         stress is greater than a predefined threshold.

According to one embodiment, the first cladding panel and the second cladding panel being in the form of a lattice, the method can additionally comprise:

-   -   installing the separator by clipping onto at least one out of: a         higher reference bar of the first cladding panel and a lower         reference bar of the second cladding panel.

DESCRIPTION OF THE FIGURES

The method which is the subject of the invention will be better understood by reading the following description of embodiments provided by way of illustration, which are in no way limited, and by observing the following drawings in which:

FIG. 1 is a schematic representation of a reinforced ground structure according to the invention;

FIG. 2 is a schematic representation of a system for positioning cladding panels according to a first embodiment of the invention;

FIG. 3 is a schematic representation of a system for positioning cladding panels according to a second embodiment of the invention;

FIG. 4 is a schematic representation of a system for positioning panels according to a third embodiment of the invention;

FIG. 5 is a schematic representation of a system for positioning cladding panels according to a fourth embodiment of the invention;

FIG. 6 is a diagram representing the development, according to the stress applied to the separator, of the spacing between the first and second cladding panels of a reinforced ground structure according to the invention.

For reasons of clarity, the dimensions of the different elements represented in these figures are not necessarily in proportion with their real dimensions. In the figures, references which are identical correspond to identical elements.

DETAILED DESCRIPTION

The present invention proposes two connect to cladding panels by means of a separator with resilient properties which are designed to permit settling of the cladding panels without forming hard points.

As illustrated in FIG. 1, the invention can in particular have an application in a reinforced ground structure 15 constituted by cladding panels. The cladding panels are generally arranged in superimposed rows, either vertically as illustrated in FIG. 1, or according to an inclined plane. The reinforced ground structure can in particular comprise a first cladding panel 1 and a second cladding panel 2. The cladding panels used in the present invention can be lattices, which can be constituted by metal bars which are woven or welded to one another. These lattices are typically constituted by galvanized metal bars, such as galvanized iron, welded to one another or interspersed in order to form a grid. A mesh of the grid thus obtained can typically have dimensions of between 2 cm×2 cm and 15 cm×15 cm. Other types of cladding panels can also be envisaged, such as composite block panels for example. The cladding panels comprise a front face and a rear face. The rear face is filled with backfill 14, which for example can be constituted by sand or rocks.

The cladding panels can comprise reinforcement elements 13, which extend from a rear face of the cladding panels into the backfill.

During construction of a reinforced ground structure of this type, the cladding panels are installed in turn, row by row, and backfill is added in order to fill the space situated on the rear face side of the cladding panels. The backfill exerts a compression force on the cladding panels which results in settling.

The invention optimizes this settling by providing a separator 31, 32, 33 between cladding panels of adjacent rows. This separator is connected both to the first cladding panel and to the second cladding panel, bringing the two panels into contact. The contact between the ends of the separator and the first and second cladding panels can take place in different ways, some of which are described hereinafter. The separator can in particular be in contact with a lower part of the second cladding panel and with an upper part of the first cladding panel. As illustrated in FIG. 1, the separator can have a first end connected to an upper reference bar 11 of the first cladding panel 1, and a second end connected to a lower reference bar 12 of the second cladding panel 2. According to the embodiment represented in FIG. 1, which will be described in greater detail hereinafter, the separator is in the form of a spring arranged in a strip 33.

The separator which is the object of the cladding panel positioning device according to the present invention can have different forms. As illustrated in the first embodiment in FIG. 2, the separator can be a conical spring 31, which is designed to be compressed completely until the space between the first and second cladding panels is reduced to a thickness corresponding to the thickness of a turn of the conical spring. The rigidity of the spring can be selected such as to permit progressive settling of the second cladding panel on the first cladding panel. Typically, the space between the two panels is initially maintained at a relative reference position Pr corresponding to a predefined length, and the separator withstands the weight of the second cladding panel without being compressed. The predefined length can typically between 2 cm and 10 cm, for example 4 cm, and can differ from one assembly to another. Beyond a predefined threshold, which for example can correspond to the weight of a mass of 10 to 20 kg or of 10 to 30 kg, the separator is compressed, and allows the first and second cladding panels to move closer together. Generally, the settling of the cladding panels can be controlled by providing a plurality of separators distributed such that two adjacent separators are separated by a meter. The properties of the separator (component material, dimensions, rigidity) can be designed to adjust the predefined threshold and the compression response of the separator under the effect of the stress exerted by the two cladding panels subjected for example to the action of the backfill.

In addition to the use of a conical spring 31, according to a second embodiment, the separator can be in the form of a bi-conical spring 32, as represented in FIG. 3. The conical 31 and bi-conical 32 springs have the advantage of being able to be compressed completely, until the space between the first 1 and second 2 cladding panels is equal to the thickness of a turn of the springs. The bi-conical spring 32 also has the advantage of providing little play when it is connected to the lower 12 and upper 11 reference bars, because of the reduced dimensions of the two ends of this spring.

Each cladding panel can comprise a bar 10 forming a recess in the form of an “L” in a lower end part of the cladding panel.

A bar 10 of this type forming a recess in the form of an “L” can contribute towards ensuring improved stability of the assembly formed by the separator and the first and second cladding panels.

In a third embodiment, the separator is in the form of a spring arranged in a strip 33. As illustrated in FIG. 4, the strip 33 has a first end 7 which is designed to be installed by being clipped onto the lower reference bar 12 of the second cladding panel 2, and a second end 8 which is designed to be installed by being clipped onto the upper reference bar 11 of the first cladding panel 1.

According to a variant embodiment, the separator can be installed such that only one of the first or second ends is clipped onto reference bars of the cladding panels.

The strip 33 also comprises curvature 9 which is designed to be supported on the bar 10 forming a reinforcement in the form of an “L”. This curvature 9 can be deformed under the effect of the stress exerted by the cladding panels subjected to the action of the backfill.

As illustrated in FIG. 5, the strip 33 ensures greater stability for the cladding panels before the backfill is added. By being supported on the bar 10, and by being connected to the lower reference bar 12 and the upper reference bar 11, the strip 33 forms together with the first and second cladding panels an assembly which limits the play between adjacent cladding panels.

The above-described separators have resilient properties which are configured to maintain a relative reference position Pr between the first and second cladding panels, until a predefined threshold has been exceeded. This predefined threshold can for example be more than, or equal to, a stress corresponding to the weight of a cladding panel. Beyond this predefined threshold, progressive resilient deformation of the separator allows the first and second cladding panels to be moved almost completely together under the effect of an increasing stress, which for example can be derived from the compression force exerted by a backfill.

The stress which gives rise to the deformation of the separator increases progressively as backfill is added to the reinforced ground structure. This stress additionally comprises the reaction force which the second cladding panel exerts on the separator, this force being substantially equal to the weight of the cladding panel.

In order to prevent premature deformation of the separator under the effect of the stress derived from the action of the backfill, it is possible to pre-stress the separator. This pre-stress can compensate for the initial force exerted by the backfill on the cladding panels. The pre-stress can be exerted by means of a connection element 5, as represented in FIG. 5. According to this fourth embodiment, the connection element 5 exerts an initial compression force which moves the first and second cladding panels closer together as far as the relative reference position Pr. In this relative reference position Pr imposed by the dimensions of the connection element, the separator is slightly compressed, and thus exerts on the cladding panels a reaction force which compensates for the initial stress exerted on the panels. This initial stress comprises a reaction force corresponding substantially to the weight of the second cladding panel, and a compression force caused by the presence of backfill above the separator.

The connection element represented in FIG. 5 is in the form of a looped hooked connector, and is associated with a separator 33 in strip form. However, this fourth embodiment can be combined with any other embodiment of the invention, and can take different forms. For example, the connection element 5 can be in the form of a metal wire, such as an iron wire, connecting the first and second cladding panels. Alternatively, a connector in the form of a “U” can also be used. Other variant embodiments which make it possible to exert an initial pre-stress maintaining a relative reference position Pr between the first and second cladding panels can be envisaged. In particular, the connection element can act as a point of attachment for reinforcement elements, which for example can be secured on the ends of the connection element.

FIG. 6 illustrates in a diagram the development of the space D between the first and second cladding panels according to the stress C exerted on the separator. Two curves are represented in a solid line in FIG. 6. The first and second curves in a solid line comprise an initial plateau 18 corresponding to an absence of deformation of the separator for any stress lower than the threshold C_(thr). This plateau illustrates the effect of the pre-stress exerted by the connection element 5, which maintains a relative reference position Pr between the first and second cladding panels. Without the pre-stress exerted by the connection element, and in the absence of any other stress, the separator would have an unloaded length Lv₁ in the case of the first curve in broken lines 16, or Lv₂ in the case of the second curve in broken lines 17. After installation of the second cladding panel on the first cladding panel, the reaction force corresponding substantially to the weight P of the second cladding panel compresses the separator until the space D reaches a value L₁ in the case of the first curve in broken lines 16, or L₂ in the case of the second curve in broken lines 17. The first curve in broken lines 16, starting from an unloaded length Lv₁ illustrates the deformation which the separator would be subjected to if it were not initially pre-stressed. The second curve in broken lines 17, starting from an unloaded length Lv₂ illustrates the deformation which the separator would be subjected to if it were not initially pre-stressed. The differences in deformation sustained according to the first and second curves in broken lines 16, 17 can typically be caused by different rigidities of spring.

It should be noted that the threshold C_(thr) represents a stress greater than that caused by the reaction force corresponding substantially to the weight of the second cladding panel. This threshold C_(thr) can also be adjusted, thus modifying the additional stress caused by the action of the backfill situated above the separator, which the separator may sustain before beginning to be deformed beyond the relative reference position Pr.

The value of the threshold stress C_(thr) can be selected for example such as to correspond to the total stress exerted on the separator when, in a reinforced ground structure, the backfill reaches a height above the first cladding panel corresponding to two cladding panels.

For stresses greater than the threshold C_(thr), the space between the first and second cladding panels is progressively reduced until it reaches a minimum value. This deformation depends on the resilient properties of the separator, which can be adjusted by means of the choice for example of the rigidity of the separator. For this purpose, the first curve 19 illustrates deformation sustained by a more flexible separator (with lower rigidity) than the separator corresponding to the second curve 20.

The cladding panels represented in FIGS. 1 to 5 are arranged vertically. However, they can also be installed on an inclined surface. In a reinforced ground structure of this type, the lattices can be disposed on a sheet of plant tissue forming a sowing support covering the topsoil. A geotextile can separate this topsoil from the backfill. In a configuration of this type, the separator can be installed in an inclined position which matches the slope of the front face of the cladding panels.

By means of the separator with the above-described resilient properties, the invention makes it possible to optimize the positioning of cladding panels, and to ensure settling thereof when they are subjected to the action of compression of a backfill. Contrary to the prior art, in order to control the settling of cladding panels, the invention does not have the risk of creating hard points liable to damage the cladding panels, and does not require subsequent removal of the separators after settling. 

1. A system for positioning cladding panels, comprising: at least a first cladding panel and a second cladding panel; at least one separator interposed between the first cladding panel and the second cladding panel, wherein the separator has resilient properties which are configured to maintain a relative reference position (Pr) between the first and second cladding panels, the separator being able to undergo progressive resilient deformation under the effect of a stress exerted on the separator by the first and second cladding panels, thus giving rise to moving closer together of the first cladding panel and the second cladding panel when the stress is greater than a predefined threshold.
 2. The system as claimed in claim 1, wherein the first and second cladding panels are lattices.
 3. The system as claimed in claim 2, additionally comprising: at least one connection element connecting the first cladding panel to the second cladding panel, the connection element being configured to exert a pre-stressing force compressing the separator and maintaining the relative reference position (Pr) between the first and second cladding panels, for as long as the stress is lower than the predefined threshold.
 4. The system as claimed in claim 3, wherein the connection element can be selected from amongst: a metal wire, a looped hooked connector, a connector in the form of a “U”.
 5. The system as claimed in claim 2, wherein the separator is in the form of a spring.
 6. The system as claimed in claim 5, wherein the spring can be able to be compressed until it reaches a thickness equal to the thickness of a turn of the spring.
 7. The system as claimed in claim 5, wherein the spring is selected from amongst: a conical spring and a bi-conical spring.
 8. The system as claimed in claim 5, wherein the spring is in the form of a strip, a first end of which is connected to the first cladding panel, and a second end of which is connected to the second cladding panel, the strip having a curvature which is a variable under the effect of the stress.
 9. The system as claimed in claim 8, wherein the second cladding panel has a bar forming a recess in the form of an “L”, the variable curvature of the strip forming a spring which is supported on said bar.
 10. The system as claimed in claim 2, wherein the separator has a first end connected to a higher reference bar of the first cladding panel, and a second end connected to a lower reference bar of the second cladding panel.
 11. The system as claimed in claim 1, wherein the predefined threshold is reached for a stress corresponding to the weight of a mass of 10 to 20 kg.
 12. A reinforced ground structure comprising a system as claimed in claim 1, the structure additionally comprising a plurality of cladding panels arranged above one another, each panel of the plurality comprising a front face and a rear face, the structure additionally comprising: backfill disposed on the side of the rear face of the panels of the plurality of cladding panels, the stress being proportional to a height of backfill in the reinforced ground structure, the predefined threshold being reached when the backfill covers a height above the first cladding panel corresponding to two cladding panels.
 13. A method for positioning cladding panels, comprising: installing at least a first cladding panel and a second cladding panel separated from the first cladding panel by a separator with resilient properties configured to maintain a relative reference position (Pr) between the first cladding panel and the second cladding panel; exerting a stress on the separator by means of the first cladding panel and the second cladding panel, such that the separator is deformed, giving rise to moving closer together of the first cladding panel and the second cladding panel when the stress is greater than a predefined threshold.
 14. The method as claimed in claim 13, wherein the first cladding panel and the second cladding panel are in the form of a lattice, the method additionally comprising: installing the separator by clipping onto at least one out of: a higher reference bar of the first cladding panel and a lower reference bar of the second cladding panel. 